This invention relates to a non-vibrating structure of an outboard motor and more particularly to an improved arrangement for avoiding and reducing vibrations of the drive shaft housing of an outboard drive.
Noise problems associated with marine outboard drives, be they outboard motors or the outboard drive portion of an inboard/outboard arrangement are well known. Normally, these outboard drives include a generally hollow drive shaft housing through which an engine driven drive shaft extends and also through which exhaust gases are discharged. Normally, the arrangement employs a muffling system within the drive shaft housing for silencing the exhaust gases. The drive shaft housing is normally a unitary casting that has a tubular shape with opposing side walls. Because of its relatively light weight construction, the side walls provide resonance elements which can actually amplify the sounds and vibrations generated within the drive shaft housing. Therefore, they can well amplify the noise of the outboard drive unit.
Although devices have been provided to attempt to silence these vibrations, the devices of the type heretofore proposed have been extremely complicated, cumbersome and have added considerably to the cost and weight of the outboard drive.
It is, therefore, a principal object of this invention to provide an improved anti-vibration device for the drive shaft housing of a marine outboard drive.
It is a further object of this invention to provide an improved and simplified arrangement for damping the vibrations of the drive shaft housing of an outboard drive.